Merus’ MCLA-129 Demonstrates Promising Single-Agent Efficiency in METex14 NSCLC in Poster Presentation at the 2024 ASCO? Annual Meeting

Merus N.V.
Merus N.V.

In This Article:

UTRECHT, The Netherlands and CAMBRIDGE, Mass., June 03, 2024 (GLOBE NEWSWIRE) -- Merus N.V. (Nasdaq: MRUS) (Merus, the Company, we, or our), a clinical-stage oncology company developing innovative, full-length multispecific antibodies (Biclonics? and Triclonics?), today announced the publication of a poster regarding MCLA-129 presented at the 2024 American Society of Clinical Oncology? (ASCO?) Annual Meeting taking place in Chicago May 31-June 4, 2024.

“These data continue to support our view that MCLA-129 is a very active drug, and that our Biclonics? platform really can create clinically active drugs for patients with cancer. We plan to start a cohort investigating MCLA-129 in combination with chemotherapy in 2L+ EGFRm NSCLC later this year,” said Bill Lundberg, M.D., President, Chief Executive Officer of Merus. “We continue to evaluate MCLA-129 with a focused investment and remain interested in a partnership to resource the further development of this asset.”

Poster presentation title: Efficacy and safety of MCLA-129, an anti-EGFR/c-MET bispecific antibody, in non-small-cell lung cancer (NSCLC) with Hepatocyte Growth Factor Receptor (c-MET) exon 14 skipping mutations (METex14)

Observations in the presentation include:

  • As of a February 16, 2024 data cutoff date, 22 patients (pts) were treated and 14 pts (64%) were continuing treatment

    • All the pts received MCLA-129 in monotherapy at the dose of 1500 mg, every 2 weeks

    • Pts received a median of 2 lines of prior therapy

    • 10 pts (45%) were tyrosine kinase inhibitor (TKI)-na?ve and 12 (55%) had received prior TKIs

    • 7 pts were excluded from the efficacy population. 4 discontinued due to AEs <2 cycles of treatment and did not experience progressive disease while on study; 3 were ongoing as of the cutoff date with <2 treatment cycles

  • 15 pts were evaluable for response having received ≥2 treatment cycles, measurable disease at baseline and ≥1 post-baseline scan

    • Response rate overall: 3 partial responses (PRs) and 6 unconfirmed PRs (uPRs) were observed by Response Evaluation Criteria in Solid Tumors v1.1 per investigator assessment; 5 of the 6 uPRs were confirmed and 1 uPR progressed after the data cutoff (8/15 confirmed PRs [53%])

    • 6 of 8 TKI-na?ve cancers responded, one of which was an initial uPR that progressed after data cutoff

    • 3 of 7 cancers with prior MET TKI responded

    • Reduction in target lesion tumor size from baseline was demonstrated in 12 pts (80%)

  • Early safety assessment in 22 pts treated with MCLA-129 monotherapy included

    • Infusion related reactions (composite term) in 86% (18% ≥ Grade (G)3)

    • One pt had treatment-related interstitial lung disease (G2)

    • Venous thromboembolism was recorded in 2 pts (1 G3 possibly treatment-related, the other G2 and not related to treatment)